To rewrite \( 9^{-23} \) as an expression with positive exponents only, you can use the property of negative integer exponents, which states that \( a^{-n} = \frac{1}{a^n} \).
Applying this property here:
\[ 9^{-23} = \frac{1}{9^{23}} \]
Therefore, the expression with positive exponents only is:
\[ 9^{-23} = \frac{1}{9^{23}} \]